: a dull constituent closely resembling charcoal that is present in banded bituminous coals and causes much of the dust in coal mines — compare clarain, durain, vitrain
History and Etymology for fusain
French, spindle tree, charcoal made from spindle-tree wood, fusain, from (assumed) Vulgar Latin fusagin-, fusago, from Latin fusus spindle; from the fact that the wood of the tree was used for spindles
